Line clamp



ly 0- J. L. YONKERS 2,206,653

LINE @LLAMP Filed Oct. 16, 1939 line and transformer. Hence, if any work must such as brass having a eye M at one e thereof 25 be done on a transformer of this type, it is neca a 11088 53 d g to a clamping Or fixed j w essaryto detach the clamp from the transmission Por n Opposite fix l W, v bo y W is line to break the connection. shaped to provide a boss ih'having a coarse Inasmuch as such clamps ar at high pobenthread it cut out therein on at least part of the 30 tials they must be handled in a suitable manner. in i surface- 1 30 Thus, it is customary to manipulate the clamp Disposed Within b S W s an y ook mi hav with a long wooden pole having suitable grips ing an eye 26 and a stem 22 to which a movable attached thereto. Such manipulation of the M 23 is l'ivfitedm W s ot able onstem 22 clamp is awkward and results in considerable and 18 adapted to cooper w fi d-jaw W egtediuly 2,1940 a 1 I 2,206,653 a 7* JIT D STATES P ,OFFICE,

w .12 (flaims. (CL 173-273) This invention relates to a line clamp for use in and which will have no tendency to" loosen up making a readily detachable contact with a due to vibration or other causes. 1' transmission line. In particular, the clamp is Referring to the drawing: adapted for making a connection between a Figure 1 shows aside-view oi the improved transmission line and some current consuming clamp; V

equipment, such as a transformer. Fig. 2 is a sectional view at right angle to Fig. As a rule every transformer or'auxiliary equip- 1 of a portion of the clamp with jaws locked to-' ment is provided with some kind of a fuse begether; tween it and the transmission line. In case of Fig. 3 is a section on line3'3 of Fig. 2; repairs on a transformer it has hitherto been the g- 4 1S a d v p 0f the threaded portion custom to open the circuit between the transof the clamp takenbetween diametral points at former anclthe transmission line by pulling out the P indicated by the a o V the fuse,or other protective device and using that Fig. 5 is a view of the movable portion f a device as a switch. Hence, clamps for establishclamp showing a modification;

ing a connection between the transformer lead Fig. ii-is afront' sectionalviewof acl mp ShOW- and that transmission line were rarely if ever i s another modification; l disturbed after installation. so that the ease or 6A is a Sectional detail o line -5 0 difllculty of removing and replacing the clamp Fi p was oi? no great consequence. Within recent g. 7 is a Sect onal View 1 0 8 down P so years, however, there has been a tendency to ent e th ea d p t Of a p Showing Still close the protective apparatus within the transanother modification; d former casing so that it is not readily accessible 3 s a Section along line M o and cannot readily be usedas a switch to break Referring to Figs- 1 t0 4 n the p 'the circuit connection between the transmission, comprises a clamp o y it of ui ablemate i l timebeing wasted as well as some danger due to to clamp a transmissio w re it. Form d len ththe long time spent upon clamp removal and wise of stem 22 is a channel or keyway 2i. A

positioning helical spring 36), preferably formed of rectangu- Generally, clamps of this type have a. pair or lar o qua e w re. a u h t is'not e e s 40 opposing jaws, one of them being movable and i po around Stem The normal 11!!- operated by a threaded member. This threaded fiensmned Pitch oi the F- y be substan" 40 member is provided with a thread of rather fine tlallr equalv o e pi c of thread It on boss gauge. The fineness of the gauge is necessary The ends 35 and of spring 30 are bent since such clamps are exposed to considerable W y toward stem 22 and engage in keyway 271 vibration which would tend to loosen up any jaw that in effect the spring is mtatably lacked to 45 operated by a coarse thread. The fineness of stem 22, while capable of expansion and contracthread,however, results in considerable time be-. 5 3 g f i mains mtgy behused. .1 ing necessary for the application andremoval ad ted w s -i g i g s of the clamp. mirthermore because oi the great up supp e en 8 c or er to provide a connection from the clamp, a raised leverage action, it is possible to screw the Jaws portion 35 is provided having a suitable channel :50

together 50 tightly as t0 damage fi therethrough for a connector 36 maintained in A l je O hi invention is to devise a wire position by a bolt 31 threaded into portion 35. clflmplwhlch a e a en 0 installed quic In order to provide a lock against accidental 1y, which will be simple, which may be applied in loosening of the clamp, as by vibration, the top amannersothat damage tothe wireis eliminated face 4 2 of boss I! is provided with aslot 43 at 56 with .top face 42 of the boss.

'tion, the locking means is effective.

Because of the coarseness of the pitch of spring 30 and thread I6 comparatively few turns of stem 22 will be necessary to withdraw jaw 23 and clear nose I2. Furthermorathe maximum compression to which wire 25 may be subjected is determined by the strength'of spring 30. As stem 22 is turned to elevate jaw 23 toward the opposing jaw I3, the turns or coils of spring 30 will climb up from boss I5 until finally the last or trailing end 32 of the spring is just above the boss. Thereafter additional turns will cause no increase in pressure since end 32 of the spring will merely idly turn relative to boss I5. It is clear that upper or leading end 3| of the spring will be prevented from moving up along the stem by the bottom of movable jaw 23. Also the lower spring end 32 will tend to wedge against the lower end of keyway 21 and positively movestem 22 downward upon jaw opening movements thereof.

Turning of stem 22 will finally cause spring end 32 to climb over protuberance 45 and fall into slot 43. In that position, spring end 32 is in v a stable position from which vibration is not apt to move it. The clamp may be loosened by turning stem 22 so that spring end 32 will be at thread end 44. This may occur whichever way the stem is turned. Normally, the easiest way is to turn stem 22 in a spring compressing direction where spring end 32 will climb up the cam surface 48 of the slot and be on face 42. Then when thread end 44 is reached by spring end 32, reverse movement of the stems will result in normal jaw release action.

Referring to Fig. 5, the stem 22' is provided with spring 30 whose top end 3| is rotatively locked to stem 22' by bending inwardly to engage .a slot 21'. Bottom end 32' of the spring is free to turn with respect to stem 22'. This modification may be used instead of movable portion of the clamp shown in Fig. 1 and is somewhat more flexible. Thus a greater departure from pitch equality of thread I6 and-spring 30' will be .tolerated since the spring end may turn in contracting or expanding. With this modifica- Thus on reverse movement of stem 22' in locked position, correspondingto Fig. 2, the lower end 32' of the spring will tend to, dig into the 'metal and hold whereas on additional movement, normally tending to increase compression (though not actually doing so), the spring will coil up tighter and pull bottom end 32 up from the slot.

In Figs. 6 and 6A-is a modification where boss I5 has a channel II of a diameter sufficient to clear spring 30". At any desired place, a pin I6 is mounted in boss I5 with the inner end of the pin extending into channel II up to stem 22. This pin I6 is thick enough to extend between adjacent coils of spring 30 and function as a thread member. .Turning of stem 22 will cause spring 30" to climb up until bottom end 32" of the spring just passes pin I6. In order to lock the clamp, spring 30 has a curved part 33 adjacent'its lower end 32". When stem 22 is turned sufliciently, pin I6 will engage part 33 and stop any normal further turning in a compressing direction.

In Figs. 7 and 8 is a modification where a spring lock washer may be used for a threaded part.

' Thus boss II5 has a channel II'I formed therethrough, said channel extending up (toward the fixed jaw) to terminate in a helical'shoulder or.

by deforming the edge of the boss metal at I44.

Channel III is large enough to accommodate both stem I22 and spring I30 while lock washer III; has its inner edge extending far enough in to engage the coils of spring I30 and assumes the position shown in Fig. 8.

A plain washer I of suitably hard metal may be disposed around stem I22 just below movable jaw I23 to act as a stop for the top coil of spring I30. Since the movable jaw is rotatable with respect to the stem, it is clear that the steel spring in turning will tend to cut it.

The modifications shown in Figs. 6 to 8 inclusive are particularly useful when the clampis tobe made of soft metal such as aluminum.

to stand up in service. But with the construc tions shown, the body of the clamp may be of aluminum while the coil spring, and either pin or lock washer may be of steel. The movable jaw may be of soft metal also in which case a steel washer may be provided.

It is obvious that the modification shown in Fig. may be used in any of the constructions shown. The locking means shown in Figs. 2 to 4 inclusive may also be used in the lock washer construction of Figs. 7 and 8.

What is claimed is:

1. A wire clamp comprising a body having a stationary jaw and an apertured portion, a member disposed in said aperturedportion and carrying a movable jaw for cooperation with said stationary jaw, said member being movable in jaw-opening and closing directions, a helical spring disposed around said member, means for looking at leastone end of said spring against rotation with respect to said member, means on said body for threadedly cooperating with the coils of said spring upon turning movements of said member to force said spring to move axially and means for transmitting said spring force to said member for jaw-opening and closing movements.

2. A wire clamp comprising a body having a stationary jaw and an apertured portion, a member disposed in said portion andcarrying a movable jaw for cooperation with said stationary portion for threadedly engaging the coils of said spring to force said spring to moveaxially upon turning movements. of said member, said spring having a leading end which first engages said engaging means upon jaw-closing movement, and

means for transmitting the axial force of said leading spring end to said movable jawupon turning movement of said member tending to close the jaws.

3. The structure of claim 2 wherein said locking means consists of a key-way lengthwise in ascents 4. A wire clamp comprising a body having a,

I stationary jaw and an apertured portion havpart adapted to cooperate to move said spring axially with respect to said portion upon member turning movements and means for transmitting the axial force of said spring to said movable jaw.

ll of the aperture and removed from the 5. The structure of claim 4 wherein said locking means consists'oi a key-way lengthwise on said member and wherein both ends of said spring are inturned to engage in said key-way.

6. The clamp of claim 4 wherein the thread part has an end face where the thread terminates with respect to jaw-closing direction and wherein said end face has a slot at the periphery of the. aperture and removed from the thread end into which the trailing end or the spring during jaw-closing movement may fall for locking.

7. The clamp of claim 4 wherein the thread part has an end face where the thread termi-' mates in a jaw-closing direction and wherein said end face has a slot at the periphery of the aperture and removed from the thread end, said slot having a steep fall and gradual rise at the ends thereof encountered by the trailing end or the spring in the order indicated with respect to jaw-- closing movement.

8. A wire clamp comprising'a body having a stationary jaw and an apertured portion having a thread part, a member disposed in said portion and'movable therein, a movablejaw car'- -ried bysaid member and movable therewith in rotation .with respect, to said mem'bensaid spring.

and thread'part adapted to. cooperate to move said spring axially with respect to said portion upon member turning movements, said thread part having an end face where the thread'termitnates with respect to jaw-closing directions, said end face having a slot therein at the periphery end and means for transmitting the axial force of said spring to said jaw for jaw, moving purposes.

9. A wire clamp comprising a body having a stationary jaw and an apertured portion, a member disposed in said portion and movable therein, a movable jaw carried by said member and movable therewith in respect to said stationary jaw in jaw-opening and closing directions, a hell ical spring disposed around said member, means for looking at least one end of said spring against.

rotation with respect to said member, at least one pin carried by said apertured portion and having an end projecting into the path of said spring with respect to longitudinal travel of said spring, said pin and being adapted to engage ad jacent spring coils whereby upon turning move ment of .said member said spring is moved asially with respect to said pin and means for transmitting the anal force of said'spg to said movable jaw.

10. The structure of claim 9 wherein the lagging end of the spring in a jaw compre direction is shaped to provide anotched portion engaging said pin for locking-purposes when said member has been turned to a position of ximum jaw closing.

11. The structure of claim 9 wherein both ends oi the spring are locked to the member against rotation with the locking means consisting oi a key-wayin the member and the spring ends bent in to engage thekey-way and wherein the lagging end of the spring in a jaw compressing direction is shaped to provide a notched portion and an abutment whereby whensaid member is tumed to close the jaws in an extreme position where said pin engages the notched portion for locking and the abutment prevents additional turning movement in the same direction.

' 12. A wire clamp comprising a body having a stationary jaw and an apertured portion, a member disposed in said portion and movable therein,

a movable jaw carried by said member and movable'therewith with respect to said stationary jaw in jaw-'opemng and closing directions, a helical spring disposed around said member. means for looking at least one end'of said spring against rotation with respect to said member, and

a split spring washer carried by said portion and forming a thread for cooperation with said spring to move said spring axially upon member turning movement, and means for transmitting the axial force oi. said spring to said movable jaw.

JOHN L. YO. 

